1. Field of the Disclosure
The disclosure is generally related to a decoder system and, more particularly, to a decoder system comprising a coding composition, a decoding composition and optionally, an erasing composition.
2. Brief Description of Related Technology
Traditionally, writing and printing apparatuses including but not limited to markers, pens, printers, typewriters, and stamps were simply used to make visual (and preferably, at least semi-permanent) records of information. More recently, however, some apparatuses have been used to “code” information, i.e., to make a record of “coded” information that is not readily visible to the eye. A sensor that generally knows where the information has been coded reveals or “decodes” the coded information by using a decoding tool. The decoding tool, which generally comprises physical or chemical means, typically causes a visible, positive image of the coded information to be formed.
For example, U.S. Pat. Nos. 5,684,069, 6,149,719, and 6,513,921 describe ink compositions capable of coding information such that the coded information is not readily visible to a non-target reader. Information recorded using such ink compositions is generally used to increase document security and/or to provide non-interfering bar coding for inventory control purposes. In each of the aforementioned patents, the coded information must be developed by ultraviolet or infrared light in order to be further processed. Irradiation of the ink compositions that make up the coded information causes the ink compositions to emit and/or absorb light, thereby making a positive image of the coded information, which is detectable using various commercially available infra-red and/or ultra-violet spectrophotometric sensors.